Many thanks for your help. much appreciated. I have updated the bios to v506 (04/15/2015 MDY) today.
It is an intermittent bug, so I'll report back after two weeks. ( If it works fine for two weeks then I expect it is fixed.) -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1535714 Title: Xorg freeze To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1535714/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : [email protected] Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp

